Appendix 5
Advanced Weld Overlay Technology for
Pressure Vessels & Boilers with presentations of
history cases in Refineries
Andrea Pacchiarotti
(Aquilex Welding Services)
Minutes of EFC WP15 Corrosion in the Refinery Industry 30 March 2006
Advanced Weld Metal Overlay
Technology for Pressure Vessels &
Boilers with presentations
of history cases
Mike Welch - Aquilex Welding Service U.S.A.
George Lai - Aquilex Welding Services Consultant
Andrea Pacchiarotti –Aquilex Welding Service s Italia
WSI EUROPE
WSI
Spijkenisse
Netherlands
Corporate Headquarters
Atlanta
Georgia, USA
25 years experience in Automated Welding
¾ Design and Build automated Welding Equipment
¾130’000 m2 of weld overlay
¾1.8 milions of Kg Wire applied
Refineries &
Chemicals
30%
Other
5%
WtE
20%
WSI EU SHOP
Tubi Rivestiti e
Pareti Membranate
Radom - POLONIA
¾ Logistic Headquarter in The Netherlands
and Manufactory Facility in Poland
¾ 600 plus trained and qualified weld operators
¾ Officies in several Countries around the world
Yearly Performances:
500 Projects
25 %
20%
Pulp & Paper
Power Generation
300 emergency on site job
20’000 m2 of weld overlay
1
• In
the past, Weld Overlay was
considered to be a temporay Repair
Solution
• Today, Weld Metal Overlay
(Unifuse® Solution by WSI) is an
advanced welding technology that
delivers Permanent Repair &
Upgrade Solutions (it permits to your
plant to reach higher performances)
What is Weld Overlay ?
Unifuse® Weld Overlay is:
A System Developed Approach to provide
Corrosion or Erosion/Corrosion Protection for
Major industrial Process & Boiler Plant
Alloy
Component Weld Overlay Applications
ER309L
External Weld Overlay for Atmospheric
Protection
ER317L
Vessel Weld Metal Overlay
Naphthenic Acid Corrosion
Monel 400
Vessel Weld Metal Overlay
HF Service Applications
Inconel 622
Inconel 625
Sulphur Corrosion Applications, Low Ph and
high Erosion application
Hastelloy C-2000
Hastelloy C 276, C 22
Low Ph agreessive chemical process protection
2205 – 2209, 312
Duplex and Super Duplex SS for Vessel Overlay
ER70S-7
Carbon Steel Build-Up for Wall Restoration
Where is weld overlay a repair / upgrade solution ?
¾ Weld Metal Build-up
One or more layers of weld metal
applied to the base metal to obtain
desired properties or dimension.
¾ Corrosion Resistant Overlay
Dissimilar weld metal deposit on base
metal to deter corrosion/erosion.
2
Unifuse® Weld Overlay
¾ Pulse Spray Gas Metal Arc Welding (PSGMAW)
¾ Higher Welding Speed compared to automatic equipments
¾ Fully Automatic & Programmable Machines
¾ Multiple Machines Operate Simultaneously
¾Consistent welding Parameters & Quality
¾ Broad selection of Alloys Available
¾Closed-Loop Process Control
Weld Parameter Controls
ClosedClosed-Loop Process Control
¾ GMAW: Wire Speed, Volts, AHC
¾ GTAW: Wire Speed, Amps, AVC
¾ Deposition Rate
¾ Heat Input
¾ Bead Placement
3
Microstructure Density
Alternative
Unifuse® Quality
Composition
1. Homogenous Overlay, < 7% Diluition
2. Fusion Boundary, < 10 - 12% Diluizione
3. Metallo Base
Unifuse® weld overlay
Process Characteristics
Unifuse® 180
Unifuse® 360
SMAW
Total Heat Input
(Joules/Sq.Ft)
450,000
400,000
1,600,000
Thickness
Tolerance (mm)
.010
.005
0.20
Low .010
Low .010
Smooth
Extremely Smooth
Depth of HAZ
(mm)
Surface Profile
High .040
°
Rough
* Alloy 625, wire data
Temperature
(°C)
Tensile
Strength
MPa
Yield
Strength
at 0.2%
Elongation in
2.0 in.
Room
786 (905)*
460 (490)*
54 (48,5)*
315
660
383
45
426
645
376
53
537
614
360
48
650
600
354
42
4
Pressure Vessel Solutions
Reliability Considerations
• Environmental Driven Modifications
• Feed Stock Changes
• Design Modifications
• Life Extension
• Corrosion Under Insulation (CUI)
5
Options?
• Component Replacement
• Mechanically Bonded Linings (No
Restoration Strength)
–Refractory
–Thermal Spray
–Strip Lining
• Manual “Pad” Welding
The WSI Solution
Unifuse
®
6
What is Unifuse®?
• Unifuse® is:
– A Comprehensive Program for Delivering Optimized
Automated Weld Overlay Performance Properties.
Vertical Down
Horizontal
Unifuse® Technology
• Applies optimal weld
chemistry
– Controls all weld parameters
– Lowest dilution achievable
– Real-time display
• Recent improvements
– PLC Controlled
– Proportional Automatic
Height Control
– Proprietary Wire Feed
System
– Watchdog system
7
Unifuse® Technology
• Applies optimal weld
chemistry
– Controls all weld parameters
– Lowest dilution achievable
– Real-time display
• Recent improvements
– PLC Controlled
– Proportional Automatic
Height Control
– Proprietary Wire Feed
System
– Watchdog system
Typical Applications
•
•
•
•
•
•
•
•
•
•
•
Vessels
Towers
Columns
Bottom & Top Heads
Transitions
Nozzles
Heat Exchangers
Horizontal Drums
ID Piping
OD Piping
Plate for Fabrication
8
History cases
Unifuse® for Insulation Corrosion
•
•
•
•
•
•
•
•
•
•
Facility : UK Refinery
Plant Item : Coking Vessel
Damage : Under Insulation Corrosion
Location : Knuckle of top dome
No. of Vessels : 2
Vessel diameter : 6.2 mtrs
Overlay Area : 20 m2 per vessel
Overlay thickness : Minimum 7.0 mm
Material : Carbon Steel
Program : 9 days utilising multiple automatic
welding systems
Unifuse® for Insulation
Corrosion
9
Repair of Solvent
Dehydration Tower
BP Amoco – Decatur Refinery
Customer Challenge
• Solvent dehydration tower
• Tower details:
–
–
–
–
SA-240-316L material
165 foot tall
13 foot ID
Original wall thickness 0.800”
• Turnaround inspection:
– Reveals corrosion of bottom
section due to chemical attack
– Vessel wall thickness as low as
0.250”
• Issue:
– 62” opening in the middle of the
overlay zone
10
Customer Challenge
Client options:
• Replacement:
– Lead time: 8 months
• Pad welding:
– Already been done by general
contractor with long schedule &
poor quality
• Weld overlay concerns:
– Distortion of manway
WSI Approach
Engineered Repair Design:
• Perform Finite Element Analysis of
overlay zone
• Prediction:
– No distortion beyond design
engineered limitations
– Deflection of manway to be less than
1%
– Application methodology optimized for
safety, quality, and productivity
11
WSI Approach
• Results
• Restored pressure
boundary with two layers
of 316L
• Applied Alloy 625 over
buildup areas as well as
lower vessel section
– Model within 1% of measured
distortion
– Cost savings of over $2.5
million
– Time savings of over 1 week
BP HHT-701 Dehydration Tower Predictive Distortion
Analysis Validation
156.00
155.75
155.50
155.25
Measurements after
overlaid
155.00
154.75
154.50
Predicted Distortion
154.25
154.00
0
2
4
6
8
10
12
Elevation (feet)
Horizontal Weld Overlay
Separators
12
Horizontal Weld Overlay
Horizontal Weld Overlay
13
Horizontal Weld Overlay
Automatic Overlay inside
Vessel bores and nozzles
Horizontal drum repair
BP-Amoco - Prudhoe Bay
Upstream Facility
14
Customer Challenge
•
•
•
•
•
Upstream facility in Alaska
Slug Catcher: ASME Section VIII, Div 2 pressure vessel
Corrosion on bottom 1/8 of entire vessel length
800+ square feet below minimum wall thickness
Schedule, schedule, schedule: Any downtime associated
with component shut down the entire plant
100 feet
18 feet
Customer Challenge
Client options:
• Pad Weld:
– Schedule: unknown
– Quality: unknown
– Post weld heat treatment required
• Automated Unifuse weld overlay
– Schedule: less than 40 days worst case
– Quality: Unifuse technology
– Post weld heat treatment eliminated
through temper bead
• WSI Welding Engineering developed
appropriate weld procedures
15
WSI Solution
Weld procedures:
• Groove
– Temperbead GMAW buildup with
ER70S-7 (2 layers)
– GMAW buildup with ER70S-7 (1
layer) & ER309LSi temperbead
– SMAW E7018-H4 buildup on
nozzle/shell intersections
• Corrosion-resistant overlay
– GMAW ER309LSi
– GTAW ER309L for nozzle
overlays
WSI Solution
Implementation Plan:
• Vessel prepared by others
– Internals removed, hydrogen bakeout
• Sandblast vessel
• Perform visual & UT inspection
• Surface preparation by grinding and
gouging
• Perform weld metal build-up
– Areas requiring one layer of 70S-7 buildup
uses one layer of ER309Lsi for tempering
(shown on the right)
– Areas requiring two layers of 70S-7 buildup
uses 70S-7 for temperbead
• Perform visual & UT inspection of buildup
areas
• Perform ER309LSi overlay on areas:
– Two layers of 70S-7
– No base metal buildup
70S-7
ER309LSi
ER309LSi
16
WSI Solution
Results:
• Schedule: work
completed in vessel in
only 34 days
• Production loss nominal
based on project
occurring during a
planned turnaround
• Zero wall wastage to date
Weld overlay repair of high
pressure separator vessel
ChevronTexaco
El Segundo Refinery
17
Customer challenge
• VRDS Plant
(Vacuum residuum
desulfurization)
• Critical component in
unit
• High Pressure
Separator
–
–
–
–
SA 516, Grade 70
6’ diameter
43’ tall
5.5” thick
Customer challenge
Customer issue:
• Belzona installed 18 months
earlier
• Visual inspection reveals
Belzona is falling off
• Bottom third of vessel
requires repair
• Wall thickness below t-min
• Schedule, schedule,
schedule
18
Partial Customer List
Allied Signal
ConocoPhillips
Lyondell Chemical
Amerada Hess
Eastman Chemical
Marathon Ashland
Aristech Chemical
Equistar
Methanex
Arizona Chemical
ExxonMobil
Millennium Chemical
BASF
Farmland Industries
Monsanto Chemical
Bayer Chemical
Flint Hill Resources
Noveon
BP Amoco
Formosa Plastics
Oxychem
Chalmette Refining
GE Plastics
PDVSA
ChevronTexaco
Goodyear
Pennzoil
ChevronPhillips
Hunt Refining
Phillips 66
Citgo Petroleum
Huntsman Chemical
Tesoro Petroleum
Clark Refining
LaRoche
Shell Oil
Coastal USA
Linde Gas
Sunoco
Coastal Aruba
Motiva
Valero
WSI Solution
• Client contacts WSI
– WSI on-site in 48 hours with
supervision
– Equipment on-site within 72
hours
• High preheat of 250ºF
required
– Safety plan developed to
ensure safe work
environment
19
WSI Solution
• Project Execution
– Removed Belzona by grit
blasting
– Grinded out pits
– Performed weld buildup on
150 ft2
– Provided corrosion resistant
overlay on 300 ft2
• Executed project in 10
days
Catalyst Tube Flange
Repair
Suncor – Sarnia Refinery
20
Customer Challenge
• Methane Steam Reformer
Furnace
– 156 HP35 Catalyst 3” Tubes
• Client Issue: Cracking of
Lower Flange weld
– HP35 to Carbon Steel
– Limited access for manual
welding
– Caused by low temperature
condensation – resulting in
oxidation
Customer Challenge
• Additional concerns
– Cracking in the original weld
– Corrosion around original
weld area
• Client options
– Complete replacement of
catalyst tubes
– Dismantle lower furnace to
create access for manual
welding
– WSI approach
21
WSI Solution
WSI Alternative:
• Perform weld from the
inside of the tube
3”
– Utilize ID machining tool
– Cut existing flange and
perform new weld prep
in one step
– Install new flange with
auto GTAW ID weld
head
WSI Solution
WSI Approach:
• Developed an integrated
tool to perform the
machining and welding
• WSI used a consumable
insert to make the root pass
• Equipment is not
commercially available for
purchase
22
WSI Solution
Results:
• Inspections showed 77 flanges
needed to be replaced
• WSI handled all machining and
welding
• Four integrated systems completed
the work in 4 days
• ID of tube weld overlaid with alloy
625 with same system
• Zero rejects
Heavy Wall Piping
• Seamed hot reheat
piping replacement
• P-91 material
• Worked performed
from 2000 to 2002
• 170 Critical joints
– Ranged from 18”
diameter to 32”
diameter
– Three small rejects
23
Partial Customer List
Allied Signal
ConocoPhillips
Lyondell Chemical
Amerada Hess
Eastman Chemical
Marathon Ashland
Aristech Chemical
Equistar
Methanex
Arizona Chemical
ESSO Refinery
Millennium Chemical
BASF
ExxonMobil
Monsanto Chemical
Bayer Chemical
Farmland Industries
Noveon
BP Amoco
Flint Hill Resources
Oxychem
Chalmette Refining
Formosa Plastics
PDVSA
ChevronTexaco
GE Plastics
Pennzoil
ChevronPhillips
Hunt Refining
Statoil
Citgo Petroleum
Huntsman Chemical
Tesoro Petroleum
Clark Refining
LaRoche
Shell Oil
Coastal USA
Linde Gas
Sunoco
Coastal Aruba
Motiva
Valero
24
Appendix 6
Thermal spray coatings
Dave Harvey (TWI)
Minutes of EFC WP15 Corrosion in the Refinery Industry 30 March 2006
EFC-NACE Italia Section Joint
Meeting, Venezia 31 March 2006
Thermal Spray Coatings
David Harvey
dave.harvey@twi.co.uk
tel +44 1223 891162
Thermal Spraying
Wire
Electric arc
Powder
Flame
1
TSCs for Corrosion Mitigation
• “Anodic” materials
such as Al, Zn etc
protect carbon steel
• “Noble alloy”
coatings must
provide a physical
barrier between
substrate and
corrosive medium
Galvanic
series
HVOF Stainless Steel 316L Coatings
JP5000 316L
JP5000 Ni 625
DJ 316L
DJ Ni 625
2
Ni Alloy Coatings
Surface after corrosion testing
Stainless Steel 316L
600
Potential, mV SCE
400
Wrought
SS 316L
Eb
200
JP
0
Eb
TG
-200
DJ
HV
-400
-600
0.0001
0.001
0.01
0.1
Current density, mA/cm
1
10
2
3
Ni Alloy 625
800
JP
600
Potential, mV SCE
DJ
400
Wrought
nickel 625
200
HV
TG
0
-200
-400
-600
0.0001
0.001
0.01
0.1
1
10
Current density, mA/cm2
Pitting corrosion in substrate
Test cell position
Coating /
substrate
interface
4
Nickel Alloy 625 Coatings
Localised
corrosion attack
of coating
extending along
interinter-particle
(splat) boundaries
No penetration through coating or corrosion of
underlying steel substrate (in this example)
Spray Technology Position
Particle velocity
Cold spray
Cool HVOF
/ Warm spray
Finer particle size
Conventional
HVOF
Increased thrust
Lower heat input
Arc, flame,
plasma
Particle temperature
5
Fine Powder Cool HVOF (C-CJS)
• Very fine powders
• Very high particle
velocity
• H2 atomised
kerosene fuel
• Lower power 80kW
ID CoolFlow Internal HVOF Process
• Superfine powders
need less thermal
energy
• Shorter stand-off
distance
6
Cold Spray System
Powder
feed unit
Powder Feed
Pressurised Gas
Supersonic
Flow
Cu coating
Gas heater
(induction coil)
High pressure,
high flow gas
supply
Carrier
gas
supply
Ti coating
Mitigation of Corrosion using Thermally
Sprayed Aluminium (TSA)
7
TSA Joint Industry Projects
• Current & completed projects: (primarily offshore)
– JIP 13458: Improving the reliability and cost performance of
TSA on C-steel (completed April 2003)
– JIP 14661: TSA coatings for prevention of corrosion of 22Cr
DSS at elevated temp. (completed May 2005)
• Use of TSA to mitigate CUI for 22Cr DSS and 316L SS
– PR 9232: TSA coatings for prevention of corrosion & EAC of
welded CRAs (25Cr SDSS, 22Cr DSS, 12Cr SMSS, 316SS)
• New projects - most relevant to the Refinery Industry:
– PR 9483: Prevention of corrosion under insulation (CUI) of
steel with TSA (launch May 2005)
– PR 10419: Thermal spray coatings for corrosion mitigation:
State-of-the-art (launch May 2005)
JIP13458: Thermal Spray Process
Benchmarking Study
Flame Spray
Arc spray
Purecoat
Spray jet
Shielding
inert gas
Gas
shroud
Arc jet
Plane of substrate
Arc point
Inert gas
Air
Conventional systems
New systems
HVOF wire
8
JIP 13458 & JIP14661:
Performance of Sealed TSA Coatings
Polyamide epoxy sealant
TSA
Substrate
Aluminium silicone sealant
TSA
Substrate
Ecorr and Corrosion Rate of TSA
-400
-600
Corrosion Rate
0.10
-600
-800
0.10
Ecorr
-800
-1000
Ecorr
0.01
-1000
-1200
0.01
Calc.
Corrosion
rate
Calc.
Corrosion
rate
Potential
0.00
0
5
0
5
-1200
-1400
-1400
-1600
10
15
20
25
30
10
Time (days)
15
20
25
30
0.00
Ecorr (mVsce)
Ecorr (mVsce)
LPR Calc.
Rate (mm/yr)
LPR Corrosion
Calc. Corrosion
Rate (mm/yr)
-400
-1600
Time (days)
• Ecorr ~ 1050mVsce and CR of TSA stabilise after about 15-20 days
• Stable corrosion rate of TSA ~ 6-8µm.yr-1 in seawater at 80°C, pH 7.8-8.0
9
HISC Test
Connection
Connection to
to
potentiostat
Potentiostat
Extensometer
Extensometer
Section of failed
sample - no TSA
Test
Tensile
specimen
specimen
Pt anode
Pt anode
Reference
Reference
cell cell
Rubber seal
Rubber
seal
TSATSA-coated sample with simulated damaged
JIP13458: High Temperature Seawater
Test Rig
Cold
saltwater
Control room
Freezer room
Hot oil
tank
Water level
Sand level
10
TSA Review - Joint Industry Project
• PR10419: Thermal spray coatings for corrosion
mitigation: State-of-the-art (launch May 2005)
• Objectives:
–
–
–
–
•
State-of-the-art report, experience, concerns
Best practice guidelines
Benchmark technically & economically
Identify technology gaps
Work scope:
–
–
–
–
–
Assets and components
Service duty and environment
Standards and codes of practice
Thermal spraying processes & materials
Application issues, health & safety and environment, QA/QC
11
Appendix 7
The role of technical societies and working
parties in the management of knowledge
Giovanna Gabetta (ENI E&P)
MarinoTolomio (VeneziaTecnologie)
Minutes of EFC WP15 Corrosion in the Refinery Industry 30 March 2006
The role of technical societies
and working parties
in the management of knowledge
Giovanna Gabetta, Eni Div. E&P
Marino Tolomio, VeneziaTecnologie
Refinery Corrosion Working Party
EFC & Nace, Italy Section
March 31, 2006
LS
Knowledge Management
•New
information
systems
and
tools,
new
communication facilities increase the amount of
information available at a speed that was not
conceived until a few years ago
•Increasing importance to “intangible assets” and
knowledge - essential for the competitive advantage
•There is a need to find, select, organize, elaborate,
and present information in a way that improves the
performance of employees and organizations in a
specific area of interest
LS
1
•Knowledge management (KM) helps an organization
to gain insight and understanding from its own
experience
•Specific KM activities help focus the organization on
acquiring, storing, and utilizing knowledge for such
things as problem solving, dynamic learning, strategic
planning, which are in summary a support to decision
making
LS
KNOWLEDGE
• Explicit, or Codified Knowledge: information and rules mainly in written
form, as for instance project reports, contracts, process diagrams, lists,
and explanations of lessons learnt and case studies, with books,
manuals, company standards, and best practices, in summary
documents and publications easily searchable, in addition to data and
information with high added value, particularly those which come from
experience internal to the system.
• Tacit, or Personal Knowledge is not codified, difficult to become formal,
based on practical experience, short-lived and volatile. It is based in the
knowledge patrimony of people, and people only can make it explicit via
direct contact with other people. It is a weak but important asset of the
company culture, since it is above the behaviour of the company
members.
• Explicit knowledge is estimated to be only about 20% of the total
amount of knowledge in a company. The remaining is tacit knowledge,
which is normally shared only for a small amount. One of the important
challenges of KM is to provide tools to share the tacit knowledge, which
is a personal asset of the human beings in a company
LS
2
Collect and share knowledge
• Explicit knowledge can be managed inside an Information and
Communication Technology (ICT) system.
• To manage tacit knowledge, people must communicate: informal
and individual networks connecting people, helping to solve the
daily problems
• Unfortunately, often no track record remains of such knowledge
exchanges (typically, they happen verbally and/or by phone,
without recording)
• There is a need of organizing the knowledge. There is a need for
places where
tacit knowledge can become esplicit
LS
KM Systems
• Knowledge Management systems are aimed at facilitating and
speeding up the sharing of best practices, lessons learned, and
other know how inside the organizations
• The above systems are based on ICT tools (portals, data bases,
research engines) to organize and present explicit knowledge
• Virtual Communities help to
• Virtual Communities are groups of people who interact using
information tools (e-mail, chat, video conferences and so on)
having a possibility to record and retrace the contacts; they help
building relationships between people and sharing esplicit
knowledge
LS
3
Communities of practice
• Communities of Practice (CoP) are virtual
communities made up of people who share a passion
for something that they know how to do and who
interact regularly to learn how to do it better
• Communities facilitate and speed-up the sharing of
best practices, lessons learned and other ‘know how’
across the organisation
LS
Workflow for a Problem Solving Community
Problem!
/
Searching
(tacit)
CoP Member
Notification
+
Dispatching
User / Professional
Central Explicit
Knowledge Database
Solution
Submission
e-mail
CoP Mailbox
Procedures
Standards
Best Practices
MyDoc
:::::::::
Answers
on
experience
CoP Member
e-mail
e-mail
Solution!
automatically
dispatches to ...
Answers on
experience
Answers on
experience
+
search in
the KDB
• Sorry ….
• Try …..
• Solution is….
• Do not try….
• Sorry ….
• Try …..
• Solution is ….
• Do not try….
• Sorry nothing in KDB
• Solution found in KDB
User/Professional
e-mail
Collaboration
Netmeeting, ….
e-mail
CoP Member
e-mail
e-mail
CoP Leader
( Enabling Team
Representative )
Answers
on
experience
+
search
in the KDB
Searching
( tacit + explicit )
CoP Members
Validation
e-mail
Notification
e-mail
e-mail
After Action Report
Submission
CoP Leader
a) Inserting
BP
in prevalidated
KDB
b) Inserting
Validated
BP
MyDoc
ACL
Workflow
Central Tacit
Knowledge Database
Central Tacit
Knowledge Database
LS
4
WHY A MATERIALS CoP?
The importance of being a “User” of materials
- mainly of structural materials – is
nowadays growing in the industry
In Eni Group, competencies on materials are
widespread and transversal
LS
FACTORS OF IMPORTANCE
• Increasing severity of the environment for new installations (deep
water, permafrost…)
• Increasing aggressiveness of crude oil(water cut, sulphur content)
• Increasing age of plants and components
• Strategic importance of operating plants worldwide
• New aptitude – especially in Europe and US – toward the
responsibility of Users in Health, Safety and Environmental issues
Experience and knowledge in the field of Materials are necessary to
support decision
• Design
• Inspection
• Maintenance
• problem shooting
• fitness for service…
LS
5
Money spent somewhere can be saved elsewere
Problemsmistakes
TechnologyInnovation
Preventive
actions
Collecting and
sharing
experience: CoP
Materials
Good management and organization
OPTIMIZATION
LS
Members of the Materials Cop have an experience in:
Materials properties
Inspection and control
Risk assessment
Damage mechanisms and their prevention
Corrosion Management
LS
6
Mission of the CoP “Materials”
• Promote and support development and
diffusion of knowledge in the field of structural
integrity of materials for oil & gas industrial
plants
• Realize a survey of needs and resources inside
the Group
• Implement and share the Group experience
Data base
LS
CoP boundaries
• Domain: the definition of the area of shared
inquiry and of the key issues
• Community: the relationships among
members and the sense of belonging
• Practice: the body of knowledge, methods,
stories, cases, tools, and documents
LS
7
A space for a CoP
Space for meetings (physical)
Space for relationship
portal, mail
(interaction, emotion, thinking)
Tacit Space
ideas, proposals
(creativity, proactivity, energy)
LS
CoPs and scientific associations
• Can a scientific association be a CoP?
• Small groups of specialists (named Technical Committees,
Working Parties or the-like..) who meet regularly and
organize events
• Web site and communication via mail
EXAMPLE
• The European Federation of Corrosion is organized in
Technical Committees (TCs)
• Each of these TCs focuses on selected aspects of corrosion
and attracts experts from all over the world
LS
8
The role of associations
• Associations and TCs can act as a
Knowledge Management System with the
objective of facilitating and speeding-up the
sharing of best practices, lessons learned
and other ‘know how’ across the scientific
community
LS
FUTURE WORK
• The contribution to a KM system by a TC such
as Refinery corrosion group could be:
• Realizing a survey of needs and resources;
• Preparing, implementing and sharing an
experience Data Base
• Support the creation and successful life of the
international network.
LS
9
CONCLUSIONS
• The Management of Knowledge and the
solution of complex technical problems in a
global world is an important challenge for the
future. The contribution of existing networks
such as technical associations and Working
Parties (Communities of Practice) is very
important to enhance the cooperation
between scientists and experts all over the
world
LS
10
Appendix 8
Cases of failure analysis in industrial plants
Sergio Volontè (Tecnimont)
Minutes of EFC WP15 Corrosion in the Refinery Industry 30 March 2006
Case of failure analyses in industrial plants
HEAT EXCHANGER KETTLE TYPE: CORROSION OF THE TUBE BUNDLE
Author
dr. Sergio Maria Volonté
Corrosion & Painting
Group Leader
Case of failure analyses in industrial plants
z
ITEM: KETTLE USED AS EVAPORATOR
z
FLUID
SHELL SIDE: WATER SOLUTION OF POTASSIUM CARBONATE
in 3.6% (pH = 8.3) → out 18.1% (pH = 10.7)
TUBE SIDE: PROCESS GAS
z
OPERATING CONDITIONS
TEMPERATURE (PRESSURE) SHELL SIDE: 145 °C (5.3 bar g)
TEMPERATURE (PRESSURE) TUBE SIDE: in 250 ÷ out 156 °C (32 bar g)
z
MATERIAL OF CONSTRUCTION: STAINLESS STEEL UNS S30400
z
TUBE - TUBE SHEET JOINT: STRENGTH WELDING PARTIALLY
MECHANICAL EXPANDED WITHOUT GROOVES
z
FAILURE PLACE: FREE SURFACE LOCALIZED BETWEEN THE TUBE
AND THE TUBE SHEET, SHELL SIDE
z
SERVICE LIFE BEFORE FAILURE: 2 MONTHS
1
Case of failure analyses in industrial plants
KETTLE:
KETTLE:GENERAL
GENERALSKETCH
SKETCH
Case of failure analyses in industrial plants
THE
THETUBE
TUBESURFACE
SURFACEUNDER
UNDERTHE
THETUBE-SHEET
TUBE-SHEETWAS
WASFOUND:
FOUND:
- - PART
PARTOF
OFTHE
THE TUBE
TUBE MECHANICALLY
MECHANICALLYEXPANDED
EXPANDED (ABOUT
(ABOUT 60
60 mm):
mm): BRIGHT
BRIGHT AND
ANDTHE
THE
THICKNESS
THICKNESSEXTREMELY
EXTREMELYTHIN.
THIN.
- - PART
PART OF
OF THE
THE TUBE
TUBE NOT
NOT MECHANICALLY
MECHANICALLY EXPANDED
EXPANDED (ABOUT
(ABOUT 80
80 mm):
mm): MATT
MATT AND
AND
FREE
FREEFROM
FROMCORROSION.
CORROSION.
SURFACE
SURFACENOT
NOT
MECHANICALLY
MECHANICALLY
EXPANDED
EXPANDED
SURFACE
SURFACE MECHANICALLY
MECHANICALLY
EXPANDED
EXPANDED
2
Case of failure analyses in industrial plants
DETAIL
DETAILOF
OFTHE
THEPREVIOUS
PREVIOUSPHOTO:
PHOTO:THE
THEBREAKING
BREAKINGHAPPENED
HAPPENEDDURING
DURINGTHE
THE
REMOVING
REMOVINGOF
OFTHE
THETUBE
TUBEFROM
FROMTUBE-SHEET:
TUBE-SHEET:THE
THETHICKNESS
THICKNESSWAS
WASTOO
TOOLOW.
LOW.
Case of failure analyses in industrial plants
z
-
TESTS AND RESULTS CARRIED OUT IN THE LAB:
CHEMICAL ANALYSIS OF THE MATERIAL OF CONSTRUCTION:
CONFIRMED THAT WAS UNS S30400
METALLOGRAPHIC EXAMINATION: CONFIRMED THAT:
THE MATERIAL USED FOR CONSTRUCTION WAS PLACE IN
SERVICE SOLUTION ANNEALED
THE SURFACE INTERESTED BY CORROSION SHOWED A
“WAVED” PROFILE, FREE FROM LOCALIZED CORROSION (PITS
AND INTERCRYSTALLINE CORROSION)
CHEMICAL ANALYSIS OF THE K2CO3: THE CONTENT OF
CHLORIDES IN THE CONCENTRATED SOLUTION WAS LESS THAN
100 ppm, VALUE CONSIDERED “NEGLEGIBLE” IN ALKALINE
SOLUTION
3
Case of failure analyses in industrial plants
z
USEFUL INFORMATION
THE AQUEOUS SOLUTIONS OF POTASSIUM CARBONATE, WHEN
OVERHEATED, ARE SUBJECTED TO HYDROLISIS PRODUCING
POTASSIUM HYDROXIDE AND CARBON DIOXIDE.
THE CHEMICAL REACTION IS THE FOLLOWING:
K2CO3 + H2O → 2 KOH + CO2
THE NEXT TABLE, ONLY AS EXAMPLE, SHOWS THE RATE OF
DECOMPOSITION OF AN AQUEOUS SOLUTION 0.2N OF K2CO3
BOILED UNDER REFLUX AT ATMOSPHERIC PRESSURE.
Case of failure analyses in industrial plants
KK2CO
3 0.2N
2CO3 0.2N
CORRESPONDS
CORRESPONDS
TO
TO2%
2%w/w,
w/w,THIS
THIS
VALUE
VALUEOF
OF
CONCENTRATION
CONCENTRATION
IS
ISCOMPARABLE
COMPARABLE
TO
TOTHE
THEKETTLE
KETTLE
FEED
FEEDAQUEOUS
AQUEOUS
SOLUTION
SOLUTION
8180
8180minute
minute
CORRESPOND
CORRESPOND
TO
TOLESS
LESSTHAN
THAN66
DAYS
DAYS
FROM:
FROM:MELLOR’S
MELLOR’S––COMPREHENSIVE
COMPREHENSIVETREATISE
TREATISEON
ONINORGANIC
INORGANICAND
AND
THEORETICAL
THEORETICALCHEMISTRY
CHEMISTRY––VOL.
VOL.IIII––SUPPLEMENT
SUPPLEMENT33––1963
1963- -LONGMANS
LONGMANS
4
Case of failure analyses in industrial plants
z
CAUSE OF THE FAILURE
THE CORROSION PRIMED ON THE TUBE SURFACE HAS BEEN
ATTRIBUITED TO THE WRONG MECHANICAL DESIGN WITH THE
FORMATION OF A CREVICE BETWEEN THE TUBE AND TUBE-SHEET.
THE HYDROLYSIS OF THE K2CO3 WITH THE PRODUCTION OF A
STRONG ALKALI SUCH AS KOH IS ONLY A CONSEQUENCE OF A
WRONG DESIGN OF THE EQUIPMENT.
IN FACT, INSIDE THE CREVICE THE FOLLOWING HAPPENDED:
- HIGH EVAPORATION OF THE WATER THAT INCREASE THE
ALKALI CONCENTRATION;
LOW REDUCTION OF THE WALL TEMPERATURE DUE TO THE
LITTLE VOLUME OF THE AQUEOUS SOLUTION.
THE MATERIAL OF CONSTRUCTION: UNS S30400, IS CHARACTERIZED
BY ACTIVE / PASSIVE BEHAVIOUR.
FROM LITERATURE, AT TEMPERATURE HIGHER THAN 150 °C,
CONCENTRATED SOLUTIONS OF KOH CAUSE HIGH CORROSION
RATE OF UNS S30400 (ACTIVE BEHAVIOUR).
Case of failure analyses in industrial plants
z
1.
2.
z
ADOPTED SOLUTIONS
EXTENSION OF THE MECHANICAL EXPANSION OF THE TUBE FOR
ALL THE THICKNESS OF THE TUBE SHEET. THIS MODIFICATION
HAS AVOIDED THE PRESENCE OF THE CREVICE.
INSERTION OF FERRULES INSIDE THE TUBES FOR REDUCING THE
THERMAL CONDUCTIVITY IN CORRESPONDANCE OF THE TUBE
SHEET.
FEED-BACK FROM FIELD
THE HEAT EXCHANGER HAS BEEN IN OPERATION FOR AT LEAST
TWO YEARS (PERIOD WHICH TECNIMONT HAS PROVIDED
ASSISTANCE TO CLIENT) WITHOUT ANY FAILURE.
5
Case of failure analyses in industrial plants
z
1.
2.
z
OTHERS POSSIBLE SOLUTIONS SUCH AS:
JOINT TUBE SHEET - TUBE BY BORE-WELDING (THAT IS A BUTT
WELDING BETWEEN THE TUBE SHEET AND THE TUBE);
CHANGE OF THE MATERIAL OF CONSTRUCTION TO NICHEL OR
ITS ALLOYS;
HAVE BEEN CONSIDERED TOO MUCH EXPENSIVE FOR THE
SERVICE.
FINAL CONSIDERATIONS
THE INSERTION OF THE FERRULES AND THE EXTESION OF THE
MECHANICAL EXPANSION HAVE SOLVED DEFINETELY THE
ORIGIN OF THE FAILURE.
6